Per Kurt Schwartz: Sorry to be a stickler, but the B-17 was called "Flying
Fortress."  A Stratofortress is the B-52.

A Google search turned up both the terms "Stratofortress" & "Flying
Fortress" for the B-17 bomber.  Sort of analogous to a "yellow-rumped" & a
"butter-butt," don't you think?

- Tom Marko